If the calculus turns far enough out of his favor he will throw the Enviros under the bus and agree to build the pipeline. It will make him look like a hero. He was probably planning to do it after the election anyhow.
And he has a long track record of throwing his friends under the bus when they become too politically inconvenient.
The other thing he will do is hold Stalinist show trials for Grrrrreeedy Oil Speculators in order to placate the OWS crowd.
You have read “Alinsky” and “Mao”, I see.
So have they.